For faithful transmission of genetic information during cell division, all chromosomes need to be encapsulated into a single daughter nucleus, but the underlying molecular mechanism is poorly understood. Ohsugi et al. in Tadashi Yamamoto’s Lab demonstrated that Kid/Kinesin-10, a chromosome-associated kinesin-like motor protein known as chromokinesin, contributes to this event. By analyzing mice and cultured cells lacking expression of chromokinesin Kid, they show that Kid deficiency causes defects in compact clustering of the anaphase chromosomes. This often leads to micro- or multinuclear formation at oocyte meiosis II and the first couple of mitoses after fertilization, causing embryonic death in mice. Later somatic mitoses are not fatally affected by the absence of Kid, suggesting that cell divisions under significant influence of the ooplasm specifically require Kid to prevent formation of multinucleated cells.

Program members
Tadashi Yamamoto (Division of Oncology, Institute of Medical Science)